12.2.2.6 Long trip signal
In normal circumstances the trip command resets quickly due to fault clearing. The
user can set a maximum trip pulse duration tTrip. When trip signals are longer, the auto-
reclosing open time is extended by tExtended t1. If Extended t1 = Disabled, a long trip
signal interrupts the reclosing sequence in the same way as a signal to input INHIBIT.
AND
AND
AND
initiate
PLCLOST
AND
Extend t1
long duration
ANSI05000783_2_en.vsd
pickup
Extended t1
AND
(block SMBRREC)
OR
0
0-tTrip
ANSI05000783 V2 EN
Figure 316: Control of extended auto-reclosing open time and long trip pulse detection
Reclosing checks and the reset timer
When dead time has elapsed during the auto-reclosing procedure certain conditions
must be fulfilled before the CB closing command is issued. To achieve this, signals are
exchanged between program modules to check that these conditions are met. In three-
phase reclosing a synchronizing and/or energizing check can be used. It is possible to
use a synchronism check function in the same physical device or an external one. The
release signal is configured by connecting to the auto-reclosing function input SYNC.
If reclosing without checking is preferred the SYNC input can be set to TRUE (set
high). Another possibility is to set the output of the synchronism check function to a
permanently activated state. At confirmation from the synchronism check, or if the
reclosing is of single-phase or two-phase type, the signal passes on. At single-phase, two-
phase reclosing and at three-phase high-speed reclosing started by RI_HS,
synchronization is not checked, and the state of the SYNC input is disregarded.
1MRK505222-UUS C Section 12
Control
637
Technical reference manual
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